The invention is related to a lamp driving circuit, especially to a driving circuit and a method for preventing lamps from blasting.
As shown in FIG. 1, a conventional lamp used in a specific device such as a projector, because of the requirements on light emitting specified by the device, a lamp driving circuit 100 capable of providing a complicated driving signal is usually used to drive the lamp. In the lamp driving circuit 100, a control signal sync control input (SCI) is generated by an application specified integrated circuit (ASIC) 110. The control signal SCI is converted into a voltage level suitable for a driving module 130 to use via a voltage conversion circuit 120 and the voltage level is outputted to the driving module 130. The driving module 130 generates a driving signal for driving and controlling the lamp 140 to be turned on/off and adjusting the brightness of the lamp 140 according to a signal being received from the driving module 130.
For such the lamp, the changes of the brightness status are usually in accordance with a wave shape of a standard driving signal. However, because the lamp may be rather delicate, if the driving signal has a great deviation in wave shape with respect to that of the standard driving signal, the lamp may blast. So far, there is no solution to prevent the lamp from blasting although it is known that the deviation may lead the lamp to blast.